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Related papers: Expressiveness of Visibly Pushdown Transducers

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Transformer networks have revolutionized NLP representation learning since they were introduced. Though a great effort has been made to explain the representation in transformers, it is widely recognized that our understanding is not…

Computation and Language · Computer Science 2023-04-05 Zeyu Yun , Yubei Chen , Bruno A Olshausen , Yann LeCun

Hankel matrices (aka connection matrices) of word functions and graph parameters have wide applications in automata theory, graph theory, and machine learning. We give a characterization of real-valued functions on nested words recognized…

Formal Languages and Automata Theory · Computer Science 2016-06-28 Nadia Labai , Johann A. Makowsky

The usage of transformers has grown from learning about language semantics to forming meaningful visiolinguistic representations. These architectures are often over-parametrized, requiring large amounts of computation. In this work, we…

Computation and Language · Computer Science 2020-07-09 Prajjwal Bhargava

As an alternative to visibly pushdown automata, we introduce visibly recursive automata (VRAs), composed of a set of classical automata that can call each other. VRAs are a strict extension of so-called systems of procedural automata, a…

Formal Languages and Automata Theory · Computer Science 2026-05-12 Kévin Dubrulle , Véronique Bruyère , Guillermo A. Pérez , Gaëtan Staquet

Prompt tuning has achieved great success in transferring the knowledge from large pretrained vision-language models into downstream tasks, and has dominated the performance on visual grounding (VG). However, almost all existing prompt…

Computer Vision and Pattern Recognition · Computer Science 2023-05-22 Chenchi Zhang , Jun Xiao , Lei Chen , Jian Shao , Long Chen

Machine translation models have discrete vocabularies and commonly use subword segmentation techniques to achieve an 'open vocabulary.' This approach relies on consistent and correct underlying unicode sequences, and makes models…

Computation and Language · Computer Science 2021-12-13 Elizabeth Salesky , David Etter , Matt Post

Input-driven pushdown automata (also known as visibly pushdown automata and as nested word automata) are a subclass of deterministic pushdown automata and a superclass of the parenthesis languages. Nguyen and Ogawa ("Event-clock visibly…

Formal Languages and Automata Theory · Computer Science 2021-03-09 Mizuhito Ogawa , Alexander Okhotin

In this paper we provide a formal framework for comparing the expressive power of Behavior Trees (BTs) to other action selection architectures. Taking inspiration from the analogous comparisons of structural programming methodologies, we…

Artificial Intelligence · Computer Science 2021-04-19 Oliver Biggar , Mohammad Zamani , Iman Shames

This paper proposes visual-text to speech (vTTS), a method for synthesizing speech from visual text (i.e., text as an image). Conventional TTS converts phonemes or characters into discrete symbols and synthesizes a speech waveform from…

Most expressivity results for transformers treat them as language recognizers -- devices that accept or reject strings -- rather than as they are used in practice: as language models that generate strings autoregressively and…

Computation and Language · Computer Science 2026-05-26 Andy Yang , Anej Svete , Jiaoda Li , Anthony Widjaja Lin , Jonathan Rawski , Ryan Cotterell , David Chiang

In this paper we present VDTTS, a Visually-Driven Text-to-Speech model. Motivated by dubbing, VDTTS takes advantage of video frames as an additional input alongside text, and generates speech that matches the video signal. We demonstrate…

Computer Vision and Pattern Recognition · Computer Science 2022-03-25 Michael Hassid , Michelle Tadmor Ramanovich , Brendan Shillingford , Miaosen Wang , Ye Jia , Tal Remez

We show that the minimization of visibly pushdown automata is NP-complete. This result is obtained by introducing immersions, that recognize multiple languages (over a usual, non-visible alphabet) using a common deterministic transition…

Formal Languages and Automata Theory · Computer Science 2023-06-22 Olivier Gauwin , Anca Muscholl , Michael Raskin

The pebble tree automaton and the pebble tree transducer are enhanced by additionally allowing an unbounded number of "invisible" pebbles (as opposed to the usual "visible" ones). The resulting pebble tree automata recognize the regular…

Formal Languages and Automata Theory · Computer Science 2018-09-18 Joost Engelfriet , Hendrik Jan Hoogeboom , Bart Samwel

Syntactic Language Models (SLMs) can be trained efficiently to reach relatively high performance; however, they have trouble with inference efficiency due to the explicit generation of syntactic structures. In this paper, we propose a new…

Computation and Language · Computer Science 2025-08-20 Ryo Yoshida , Taiga Someya , Yohei Oseki

Automata operating on strings of nested brackets, known as input-driven pushdown automata, and as visibly pushdown automata, have been studied since the 1980s. They were extended to the case of infinite strings by Alur and Madhusudan…

Formal Languages and Automata Theory · Computer Science 2020-12-08 Alexander Okhotin , Victor L. Selivanov

The current modus operandi in adapting pre-trained models involves updating all the backbone parameters, ie, full fine-tuning. This paper introduces Visual Prompt Tuning (VPT) as an efficient and effective alternative to full fine-tuning…

Computer Vision and Pattern Recognition · Computer Science 2022-07-21 Menglin Jia , Luming Tang , Bor-Chun Chen , Claire Cardie , Serge Belongie , Bharath Hariharan , Ser-Nam Lim

An automaton is universal if it accepts every possible input. We study the notion of u-universality, which asserts that the automaton accepts every input starting with u. Universality and u-universality are both EXPTIME-hard for…

Formal Languages and Automata Theory · Computer Science 2012-05-15 Véronique Bruyère , Marc Ducobu , Olivier Gauwin

We consider symbolic tree automata (sta) and symbolic tree transducers (stt). We characterize s-recognizable tree languages (which are the tree languages recognizable by sta) in terms of (classical) recognizable tree languages and…

Formal Languages and Automata Theory · Computer Science 2012-08-28 Zoltán Fülöp , Heiko Vogler

Transformer-based architectures have become the shared backbone of natural language processing and computer vision. However, understanding how these models operate remains challenging, particularly in vision settings, where images are…

Computer Vision and Pattern Recognition · Computer Science 2026-04-03 Juan Manuel Hernandez , Mariana Fernandez-Espinosa , Denis Parra , Diego Gomez-Zara

Visual Prompt Tuning (VPT) is an effective tuning method for adapting pretrained Vision Transformers (ViTs) to downstream tasks. It leverages extra learnable tokens, known as prompts, which steer the frozen pretrained ViTs. Although VPT has…

Machine Learning · Computer Science 2023-06-09 Seungryong Yoo , Eunji Kim , Dahuin Jung , Jungbeom Lee , Sungroh Yoon